The present disclosure relates to a liquid crystal display with a sub-pixel configuration which includes, for example, sub-pixels of four colors including red (R), green (G), blue (B) and white (W).
In recent years, as displays for flat-screen televisions and portable terminals, active matrix liquid crystal displays (LCDs) in which TFTs (Thin Film Transistors) are arranged for respective pixels are often used. In such liquid crystal displays, typically, pixels are individually driven by line-sequentially writing a picture signal to auxiliary capacitance elements and liquid crystal elements of the pixels from the top to the bottom of a screen.
To reduce power consumption at the time of displaying a picture in a liquid crystal display, there are proposed liquid crystal displays including pixels each configured of sub-pixels of four colors in liquid crystal display panels (for example, refer to Japanese Examined Patent Application Publication Nos. H4-54207 and 114-355722 and Japanese Patent No. 4354491). More specifically, the sub-pixels of four colors are sub-pixels of red (R), green (G) and blue (B) and a sub-pixel of a color (Z; such as white (W) or yellow (Y)) with higher luminance than these three colors. In the case where a picture is displayed with use of picture signals for sub-pixels of such four colors, compared to the case where a picture is displayed by supplying picture signals for three colors R, G and B to each pixel with a three-color RGB sub-pixel configuration in related art, luminance efficiency is allowed to be improved.
Moreover, Japanese Patent No. 4354491 also discloses a liquid crystal display actively controlling the luminance of a backlight based on a display picture (based on the signal level of a picture signal) (performing a dimming process). In the case where such a technique is used, while maintaining display luminance, a reduction in power consumption and a dynamic range expansion are achievable.